反应详情

To a mixture of 4-(4-chlorophenyl)-2-phenyl-5-oxazolepropionic acid (500 mg), triethylamine (230 mg) and tetrahydrofuran (10 ml) was added ethyl chlorocarbonate (250 mg) at −40° C., and the mixture was stirred for 1 hr. Diethyl 4-aminophenylphosphonate (420 mg) was added, and the mixture was stirred at room temperature for 5 hrs. The reaction mixture was poured into water and extracted with ethyl acetate. The organic layer was washed with water, dried over anhydrous magnesium sulfate and concentrated. The residue was purified by silica gel column chromatography and 3-[4-(4-chlorophenyl)-2-phenyl-5-oxazolyl]-N-[4-(diethylphosphono)phenyl]propionamide (295 mg, yield 36%) was obtained as colorless prism crystals from a fraction eluted with ethyl acetate-chloroform (1:1, volume ratio). melting point: 139–140° C. (recrystallized from dichloromethane-isopropyl ether).

1. stirringthe mixture was stirred at room temperature for 5 hrs
2. extractionextracted with ethyl acetate
3. washThe organic layer was washed with water
4. dry with materialdried over anhydrous magnesium sulfate
5. concentrationconcentrated
6. customThe residue was purified by silica gel column chromatography